/*
 *  Copyright (C) 2010-2021 Fabio Cavallo (aka FHorse)
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
/*
 *  FIPS-180-1 compliant SHA-1 implementation
 *
 *  Copyright (C) 2003-2006  Christophe Devine
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License, version 2.1 as published by the Free Software Foundation.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *  MA  02110-1301  USA
 */
/*
 *  The SHA-1 standard was published by NIST in 1993.
 *
 *  http://www.itl.nist.gov/fipspubs/fip180-1.htm
 */

#ifndef _CRT_SECURE_NO_DEPRECATE
#define _CRT_SECURE_NO_DEPRECATE 1
#endif

#include <string.h>
#include <stdio.h>
#include "sha1.h"
#include "common.h"

/*
 * 32-bit integer manipulation macros (big endian)
 */
#ifndef GET_UINT32_BE
#define GET_UINT32_BE(n,b,i)                    \
{                                               \
	(n) = ( (ulong) (b)[(i)    ] << 24 )    \
	    | ( (ulong) (b)[(i) + 1] << 16 )    \
	    | ( (ulong) (b)[(i) + 2] <<  8 )    \
	    | ( (ulong) (b)[(i) + 3]       );   \
}
#endif
#ifndef PUT_UINT32_BE
#define PUT_UINT32_BE(n,b,i)                    \
{                                               \
	(b)[(i)    ] = (uchar) ( (n) >> 24 );   \
	(b)[(i) + 1] = (uchar) ( (n) >> 16 );   \
	(b)[(i) + 2] = (uchar) ( (n) >>  8 );   \
	(b)[(i) + 3] = (uchar) ( (n)       );   \
}
#endif

/*
 * Core SHA-1 functions
 */
void sha1_starts(sha1_context *ctx) {
	ctx->total[0] = 0;
	ctx->total[1] = 0;

	ctx->state[0] = 0x67452301;
	ctx->state[1] = 0xEFCDAB89;
	ctx->state[2] = 0x98BADCFE;
	ctx->state[3] = 0x10325476;
	ctx->state[4] = 0xC3D2E1F0;
}

void sha1_process(sha1_context *ctx, uchar data[64]) {
	ulong temp, W[16], A, B, C, D, E;

	GET_UINT32_BE( W[0], data, 0);
	GET_UINT32_BE( W[1], data, 4);
	GET_UINT32_BE( W[2], data, 8);
	GET_UINT32_BE( W[3], data, 12);
	GET_UINT32_BE( W[4], data, 16);
	GET_UINT32_BE( W[5], data, 20);
	GET_UINT32_BE( W[6], data, 24);
	GET_UINT32_BE( W[7], data, 28);
	GET_UINT32_BE( W[8], data, 32);
	GET_UINT32_BE( W[9], data, 36);
	GET_UINT32_BE( W[10], data, 40);
	GET_UINT32_BE( W[11], data, 44);
	GET_UINT32_BE( W[12], data, 48);
	GET_UINT32_BE( W[13], data, 52);
	GET_UINT32_BE( W[14], data, 56);
	GET_UINT32_BE( W[15], data, 60);

#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))

#define R(t)                                            \
		(                                                       \
				temp = W[(t -  3) & 0x0F] ^ W[(t - 8) & 0x0F] ^     \
				W[(t - 14) & 0x0F] ^ W[ t      & 0x0F],      \
				( W[t & 0x0F] = S(temp,1) )                         \
		)

#define P(a,b,c,d,e,x)                                  \
		{                                                       \
	e += S(a,5) + F(b,c,d) + K + x; b = S(b,30);        \
		}

	A = ctx->state[0];
	B = ctx->state[1];
	C = ctx->state[2];
	D = ctx->state[3];
	E = ctx->state[4];

#define F(x,y,z) (z ^ (x & (y ^ z)))
#define K 0x5A827999

	P( A, B, C, D, E, W[0]);
	P( E, A, B, C, D, W[1]);
	P( D, E, A, B, C, W[2]);
	P( C, D, E, A, B, W[3]);
	P( B, C, D, E, A, W[4]);
	P( A, B, C, D, E, W[5]);
	P( E, A, B, C, D, W[6]);
	P( D, E, A, B, C, W[7]);
	P( C, D, E, A, B, W[8]);
	P( B, C, D, E, A, W[9]);
	P( A, B, C, D, E, W[10]);
	P( E, A, B, C, D, W[11]);
	P( D, E, A, B, C, W[12]);
	P( C, D, E, A, B, W[13]);
	P( B, C, D, E, A, W[14]);
	P( A, B, C, D, E, W[15]);
	P( E, A, B, C, D, R(16));
	P( D, E, A, B, C, R(17));
	P( C, D, E, A, B, R(18));
	P( B, C, D, E, A, R(19));

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0x6ED9EBA1

	P( A, B, C, D, E, R(20));
	P( E, A, B, C, D, R(21));
	P( D, E, A, B, C, R(22));
	P( C, D, E, A, B, R(23));
	P( B, C, D, E, A, R(24));
	P( A, B, C, D, E, R(25));
	P( E, A, B, C, D, R(26));
	P( D, E, A, B, C, R(27));
	P( C, D, E, A, B, R(28));
	P( B, C, D, E, A, R(29));
	P( A, B, C, D, E, R(30));
	P( E, A, B, C, D, R(31));
	P( D, E, A, B, C, R(32));
	P( C, D, E, A, B, R(33));
	P( B, C, D, E, A, R(34));
	P( A, B, C, D, E, R(35));
	P( E, A, B, C, D, R(36));
	P( D, E, A, B, C, R(37));
	P( C, D, E, A, B, R(38));
	P( B, C, D, E, A, R(39));

#undef K
#undef F

#define F(x,y,z) ((x & y) | (z & (x | y)))
#define K 0x8F1BBCDC

	P( A, B, C, D, E, R(40));
	P( E, A, B, C, D, R(41));
	P( D, E, A, B, C, R(42));
	P( C, D, E, A, B, R(43));
	P( B, C, D, E, A, R(44));
	P( A, B, C, D, E, R(45));
	P( E, A, B, C, D, R(46));
	P( D, E, A, B, C, R(47));
	P( C, D, E, A, B, R(48));
	P( B, C, D, E, A, R(49));
	P( A, B, C, D, E, R(50));
	P( E, A, B, C, D, R(51));
	P( D, E, A, B, C, R(52));
	P( C, D, E, A, B, R(53));
	P( B, C, D, E, A, R(54));
	P( A, B, C, D, E, R(55));
	P( E, A, B, C, D, R(56));
	P( D, E, A, B, C, R(57));
	P( C, D, E, A, B, R(58));
	P( B, C, D, E, A, R(59));

#undef K
#undef F

#define F(x,y,z) (x ^ y ^ z)
#define K 0xCA62C1D6

	P( A, B, C, D, E, R(60));
	P( E, A, B, C, D, R(61));
	P( D, E, A, B, C, R(62));
	P( C, D, E, A, B, R(63));
	P( B, C, D, E, A, R(64));
	P( A, B, C, D, E, R(65));
	P( E, A, B, C, D, R(66));
	P( D, E, A, B, C, R(67));
	P( C, D, E, A, B, R(68));
	P( B, C, D, E, A, R(69));
	P( A, B, C, D, E, R(70));
	P( E, A, B, C, D, R(71));
	P( D, E, A, B, C, R(72));
	P( C, D, E, A, B, R(73));
	P( B, C, D, E, A, R(74));
	P( A, B, C, D, E, R(75));
	P( E, A, B, C, D, R(76));
	P( D, E, A, B, C, R(77));
	P( C, D, E, A, B, R(78));
	P( B, C, D, E, A, R(79));

#undef K
#undef F

	ctx->state[0] += A;
	ctx->state[1] += B;
	ctx->state[2] += C;
	ctx->state[3] += D;
	ctx->state[4] += E;
}

void sha1_update(sha1_context *ctx, uchar *input, uint length) {
	ulong left, fill;

	if (!length)
		return;

	left = ctx->total[0] & 0x3F;
	fill = 64 - left;

	ctx->total[0] += length;
	ctx->total[0] &= 0xFFFFFFFF;

	if (ctx->total[0] < length)
		ctx->total[1]++;

	if (left && length >= fill) {
		memcpy((void *) (ctx->buffer + left), (void *) input, fill);
		sha1_process(ctx, ctx->buffer);
		length -= fill;
		input += fill;
		left = 0;
	}

	while (length >= 64) {
		sha1_process(ctx, input);
		length -= 64;
		input += 64;
	}

	if (length) {
		memcpy((void *) (ctx->buffer + left), (void *) input, length);
	}
}

static uchar sha1_padding[64] = { 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
		0, 0 };

void sha1_finish(sha1_context *ctx, uchar digest[20]) {
	ulong last, padn;
	ulong high, low;
	uchar msglen[8];

	high = (ctx->total[0] >> 29) | (ctx->total[1] << 3);
	low = (ctx->total[0] << 3);

	PUT_UINT32_BE( high, msglen, 0);
	PUT_UINT32_BE( low, msglen, 4);

	last = ctx->total[0] & 0x3F;
	padn = (last < 56) ? (56 - last) : (120 - last);

	sha1_update(ctx, sha1_padding, padn);
	sha1_update(ctx, msglen, 8);

	PUT_UINT32_BE( ctx->state[0], digest, 0);
	PUT_UINT32_BE( ctx->state[1], digest, 4);
	PUT_UINT32_BE( ctx->state[2], digest, 8);
	PUT_UINT32_BE( ctx->state[3], digest, 12);
	PUT_UINT32_BE( ctx->state[4], digest, 16);
}

/*
 * Output SHA-1(file contents), returns 0 if successful.
 */
int sha1_file(char *filename, uchar digest[20], char *string) {
	FILE *f;
	size_t n;
	sha1_context ctx;
	uchar buf[1024];
	uchar i;

	if ((f = fopen(filename, "rb")) == NULL) {
		return (1);
	}

	sha1_starts(&ctx);

	while ((n = fread(buf, 1, sizeof(buf), f)) > 0) {
		sha1_update(&ctx, buf, (uint) n);
	}

	sha1_finish(&ctx, digest);

	fclose(f);

	memset(string, 0x00, 41);

	for (i = 0; i < 20; i++) {
		char hex2char[3];
		sprintf(hex2char, "%02x", digest[i]);
		strcat(string, hex2char);
	}
	return (0);
}

/*
 * Output SHA-1(buf)
 */
void sha1_csum(uchar *buf, uint buflen, uchar digest[20], char *string, int typecase) {
	sha1_context ctx;
	uchar i;

	sha1_starts(&ctx);
	sha1_update(&ctx, buf, buflen);
	sha1_finish(&ctx, digest);

	memset(string, 0x00, 41);

	for (i = 0; i < 20; i++) {
		char hex2char[3];
		if (typecase == UPPER) {
			sprintf(hex2char, "%02X", digest[i]);
		} else {
			sprintf(hex2char, "%02x", digest[i]);
		}
		strcat(string, hex2char);
	}
}

/*
 * Output HMAC-SHA-1(key,buf)
 */
void sha1_hmac(uchar *key, uint keylen, uchar *buf, uint buflen, uchar digest[20]) {
	uint i;
	sha1_context ctx;
	uchar k_ipad[64];
	uchar k_opad[64];
	uchar tmpbuf[20];

	memset(k_ipad, 0x36, 64);
	memset(k_opad, 0x5C, 64);

	for (i = 0; i < keylen; i++) {
		if (i >= 64)
			break;

		k_ipad[i] ^= key[i];
		k_opad[i] ^= key[i];
	}

	sha1_starts(&ctx);
	sha1_update(&ctx, k_ipad, 64);
	sha1_update(&ctx, buf, buflen);
	sha1_finish(&ctx, tmpbuf);

	sha1_starts(&ctx);
	sha1_update(&ctx, k_opad, 64);
	sha1_update(&ctx, tmpbuf, 20);
	sha1_finish(&ctx, digest);

	memset(k_ipad, 0, 64);
	memset(k_opad, 0, 64);
	memset(tmpbuf, 0, 20);
	memset(&ctx, 0, sizeof(sha1_context));
}

#ifdef SELF_TEST
/*
 * FIPS-180-1 test vectors
 */
static char *sha1_test_str[3] =
{
	"abc",
	"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
	NULL
};

static uchar sha1_test_sum[3][20] =
{
	{	0xA9, 0x99, 0x3E, 0x36, 0x47, 0x06, 0x81, 0x6A, 0xBA, 0x3E,
		0x25, 0x71, 0x78, 0x50, 0xC2, 0x6C, 0x9C, 0xD0, 0xD8, 0x9D},
	{	0x84, 0x98, 0x3E, 0x44, 0x1C, 0x3B, 0xD2, 0x6E, 0xBA, 0xAE,
		0x4A, 0xA1, 0xF9, 0x51, 0x29, 0xE5, 0xE5, 0x46, 0x70, 0xF1},
	{	0x34, 0xAA, 0x97, 0x3C, 0xD4, 0xC4, 0xDA, 0xA4, 0xF6, 0x1E,
		0xEB, 0x2B, 0xDB, 0xAD, 0x27, 0x31, 0x65, 0x34, 0x01, 0x6F}
};

/*
 * Checkup routine
 */
int sha1_self_test( void )
{
	int i, j;
	uchar buf[1000];
	uchar sha1sum[20];
	sha1_context ctx;

	for( i = 0; i < 3; i++ )
	{
		printf( "  SHA-1 test #%d: ", i + 1 );

		sha1_starts( &ctx );

		if( i < 2 )
		sha1_update( &ctx, (uchar *) sha1_test_str[i],
				strlen( sha1_test_str[i] ) );
		else
		{
			memset( buf, 'a', 1000 );
			for( j = 0; j < 1000; j++ )
			sha1_update( &ctx, (uchar *) buf, 1000 );
		}

		sha1_finish( &ctx, sha1sum );

		if( memcmp( sha1sum, sha1_test_sum[i], 20 ) != 0 )
		{
			printf( "failed\n" );
			return( 1 );
		}

		printf( "passed\n" );
	}

	printf( "\n" );
	return( 0 );
}
#else
int sha1_self_test(void) {
	printf("SHA-1 self-test not available\n\n");
	return (1);
}

#endif
